<!DOCTYPE html>
<html>
<head>
    <title>WebSocket Examples: Reverse</title>
    <style type="text/css">
        #connect-container {
            float: left;
            width: 400px
        }

        #connect-container div {
            padding: 5px;
        }

        #console-container {
            float: left;
            margin-left: 15px;
            width: 400px;
        }

        #console {
            border: 1px solid #CCCCCC;
            border-right-color: #999999;
            border-bottom-color: #999999;
            height: 170px;
            overflow-y: scroll;
            padding: 5px;
            width: 100%;
        }

        #console p {
            padding: 0;
            margin: 0;
        }
    </style>
    <script type="text/javascript">
        var ws = null;

        function setConnected(connected) {
            document.getElementById('connect').disabled = connected;
            document.getElementById('disconnect').disabled = !connected;
            document.getElementById('reverse').disabled = !connected
        }

        function connect() {
            var target = document.getElementById('target').value;
            ws = new WebSocket(target);
            ws.onopen = function () {
                setConnected(true);
                log('Info: WebSocket connection opened.')
            };
            ws.onmessage = function (event) {
                log('Received: ' + event.data)
            };
            ws.onclose = function () {
                setConnected(false);
                log('Info: WebSocket connection closed.')
            }
        }

        function updateTarget() {
            if (window.location.protocol == 'http:') {
                document.getElementById('target').value = 'ws://'
                    + window.location.host
                    + document.getElementById('target').value
            } else {
                document.getElementById('target').value = 'wss://'
                    + window.location.host
                    + document.getElementById('target').value
            }
        }

        function disconnect() {
            if (ws != null) {
                ws.close();
                ws = null
            }
            setConnected(false)
        }

        function reverse() {
            if (ws != null) {
                var message = document.getElementById('message').value;
                log('Sent: ' + message);
                ws.send(message)
            } else {
                alert('WebSocket connection not established, please connect.')
            }
        }

        function log(message) {
            var console = document.getElementById('console');
            var p = document.createElement('p');
            p.style.wordWrap = 'break-word';
            p.appendChild(document.createTextNode(message));
            console.appendChild(p);
            while (console.childNodes.length > 25) {
                console.removeChild(console.firstChild)
            }
            console.scrollTop = console.scrollHeight
        }
    </script>
</head>
<body onload="updateTarget()">
<noscript><h2 style="color: #FF0000">Seems your browser doesn't support Javascript! Websockets rely on Javascript being
    enabled. Please enable
    Javascript and reload this page!</h2></noscript>
<div>
    <div id="connect-container">
        <div>
            <input id="target" size="40" style="width: 350px" type="text" value="/reverse" />
        </div>
        <div>
            <button id="connect" onclick="connect();">Connect</button>
            <button disabled="disabled" id="disconnect" onclick="disconnect();">Disconnect</button>
        </div>
        <div>
            <textarea id="message" style="width: 350px">Here is a message!</textarea>
        </div>
        <div>
            <button disabled="disabled" id="reverse" onclick="reverse();">Reverse message</button>
        </div>
    </div>
    <div id="console-container">
        <div id="console"></div>
    </div>
</div>
</body>
</html>